Variable-speed apparatus



Oct 22, 1929.

VARIABLE SPEED Filed Dec. 6. 1928 A. LAUB APPARATUS 2 Sheets-Sheet Oct. 22, 1929. A 1,733,024

VARIABLE S FEED APPARATUS Filed Dec. 6, 1928 2 Sheets-Sheet 2 Patented Oct. 22, 1929 UNITED STATES ADOLF LAUB, F BASEL, SWITZERLAND VARIABLE-SPEED APPARATUS Application filed December 6, 1928, Serial No. 324,246, and in Switzerland November 3, 1928.

This invention relates to a variable speed apparatus of the kind in which the rotary movement of a driving shaft is arranged to be transmitted to a driven shaft by means of a swash plate and free-wheel or ratchet mechanism. It has for its main object to enable the speed of driven shafts to be varied gradually and smoothly from zero (condition of rest) to a maximum (direct operation).

\Vith this end in view the swash plate is arranged to cooperate with such alternately operating free-wheel or ratchet mechanisms that relieve one another during operation before the end of their operating stroke and 5 is adapted to be inclined with respect to the rotary shaft, so as to vary the amplitude of the stroke of the free-wheel or ratchet mechanisms, by means of a controlling body adapted to rotate together with the swash plate and to be moved axially from the exterior of the apparatus so as to move a cam slot or the like and actuate toothed members, so that, by moving the controlling body the swash plate is moved gradually by means 95 of the cam slot or the like and toothed members from a substantially perpendicular position with respect to the shaft in which the driven shaft is at rest to an inclined position with respect to the shaft for the purpose so of speed acceleration, and restored gradually to the perpendicular position so as to render the free wheel or ratchet mechanisms inoperative, while the controlling body is being geared with a toothed wheel on the driven shaft for direct operation.

A constructional form of the invention will now be described, by way of example, with reference to the accompanying drawings in which: Y

Figure 1 is a vertical section through the apparatus on, the line II of Figure 8;

Figure 2 is a horizontal longitudinal section thereof on the line IIII of Figure 1;

Figure 3 is a half transverse section on the line III-III of Figure 1;

Figure 4 is a sectional view of a detail on the line IVIV of Figure 1;

Figure 5 is a half transverse section on the line V-V of Figure 1;

Figure (3 is a diagrammatic longitudinal section through the swash plate and the controlling body, which are illustrated as being in the position in which they are located when the driven shaft is at rest;

Figure 7 is a similar sectional view showing the position in which the swash plate and Con: trolling body are located for the greatest stroke of the free-wheel mechanisms;

Figure 8 is a similar sectional view showing the position in which the swash plate and controlling body are located for direct operation, that is to say with the free-Wheel mechanisms inoperative;

Figures 9 and 10 illustrate details;

Figures 11 and 12 illustrate in the forward and reverse condition the arrangements provided in the free-wheel mechanisms for reversing the direction in which the said mechanisms operate under load;

Figures 13, 14, 15 and 16 illustrate the free-wheel mechanisms which are here provided in two pairs arranged on either side of a bevel gearing indicated for the sake of clearness in pairs apart from one another with corresponding connecting rods operativcly connected to the swash plate (shown diagrammatically), and are intended to serve for facilitating explanation of the action of the free-wheel mechanisms.

Referring now in detail to the drawings, 1 (Figure 2) a driving shaft and 2 a shaft to be driven, these shafts being located in the same horizontal axial plane, and rotatably mounted in a closed casing 3. A swash-plate 5 is provided on a cross journal 4 on the driving shaft 1, this plate taking part in the rotary movement of the shaft 1. At the periphery of the swash-plate 5 is a groove in which a sliding ring 6 is provided (Figures 6, 7, 8). The latter is provided on its under side with a radially extending journal 7, carrying a roller which engages in a circular arc-shaped stationary guidegroove 8.

On the driven shaft 2 (Figures 1 and 2) a bevel gearing is provided, the ,main bevel wheel 10 of which is rigidly secured on the said shaft, whilst its secondary bevel wheels 11, which are in engagement with the main wheel 10, each cooperate with a pair of free wheel mechanisms 12, 12*. One pairof freewheel mechanisms (shown in Figure 1) in order to facilitate the explanation will be referred to in the followin description as the front free-wheel mechanism and the. other, which is only illustrated in sectional view (Figure 2) will be called the rear free-wheel mechanism. I

The free-Wheel mechanisms of each pair operate uni-directionally, and both pairs of free-wheel mechanisms are so arranged with respect to their actuating operation that the main wheel 10 of the bevel gearing, for the once selected direction of movement, always receives uni-directional driving impulse only resulting, in overlapping one another, in a continuous rotary .movement of the shaft to be driven. The free-wheel mechanisms (Figure 5) each comprise an oscillating member 15 and' between the latter and the stub-axle 14 of the respective differential planet wheel, jamming rollers 16, are provided which during oscillation of the member 15 in one direc- .tion transmit movement to the wheel axle 14.

and during oscillation of the member 15 in the opposite direction, however, run freely.

The members 15 of the four free-wheel .mechanisms are caused to oscillate by the swash-plate 5. For this purpose they are connected by connectin rods 20 with four radial journals 21 in the sliding ring of the swashplate 90 apart from one another, the rods 20 being connected with the members 15 and also with the journal 21 by means of ball oints.

Between the free-Wheel mechanisms and the swash plate there is provided on the driving shaft 1 an axially movable hollow controlling body 25 adapted to rotate with the shaftand with the swash plate 5. In the interior of the body 25 two toothed segments 27 are mounted, on a cross-journal 26 of the shaft 1 on opposite sides of the latter, ig-

ures 2, 6, 7 and 8), these segments engaging with two corresponding toothed segments 28 on the cross journal 4 of the swash plate.

One of the pairs of toothed segments 27-28 is. illustrated in Figure 9. Each of the toothed segments 27 is provided with a journal 29, which extends into an angular slot 30 (Figure 10) in the controllin body 25. Upon axial movement 7 of the latter, the toothed segments 27 are, owing to the slots 30, oscillated Seven during rotation of the controllin bo y 25) first in one direction and then in the opposite direction while the controlling body 25 is moved further away from the swash plate 5 according to the desired speed,'with the result that the swash plate 5 owing to the toothed segments 28 is -moved from its perpendicular position with I respect to its axis of rotation (Figure 6) to a more and more inclined position to the axis of rotation (Figure 7 and finally back again into the perpendicular position (Figure 8). In this manner any desired inclined position movement of the free-wheel mechanisms which in the limiting position,'illustrated in Figure 7, of the swash plate is at a maximum.

Axial movement of the controlling body 25 can be effected from the exterior of the apparatus by means of a forked lever 31', which is pivotally mounted at 31 and the branches of which are connected by means of links 32 with radial journals 33 011 a sliding ring 34, which lies within a peripheral groove in the controlling body 25. The journals 33 of the sliding ring 34 also extend into horizontal guide slots 34: in thecas ing 3, these slots being parallel to the axis of the shaftl, and serving to guide the controlling body during its axial move ment.

Adjacent the controlling body 25 a toothed wheel 35 is provided for direct operation;

This latter is secured to a hollow elongation 2" (Figure 2) of the driven shaft 2, the eloiigation 2 being located in a ball-bearing in a portion 36 of the casin and serving as a seat for the ball-bearing o ,the inner'end of the driving shaft 1. An internally toothed portion 37 of the controlling body 25 cooperates with the toothed wheel 35, the object of which will be apparent by reference to the operation of the mechanism which will now be described. j

The operation of the mechanism thus far described is as follows: 7

In the position of the parts as illustrated in "Figures 1 and 6 upon rotation of the shaft 1 the shaft 2'to be driven is at a standstill. The swash plate 5 rotates freely in the sliding ring 6 and does not cause movement of the freewheel mechanisms.

If it is desired to cause rotation of the shaft 2, then the controlling body 25 is moved by means of the forked lever 31 to the right as indicated by the arrow x in Figure 1, with the result that, owing to the angular slots 30, into one arm of which the journals 29 of the toothed segments 27 extend, the latter are rotated in clockwise direction, whereby, the.

swash plate 5 is moved out of the no-lead position (Figures 1 and 6) by means of the toothed segments 28 into an inclined position with respect toits axis of rotation. When the controlling body 25 is moved through a dis- .tance such that the journals 29 of the toothed segments 27 are located at the angleof the slots 30, the swash plate 5 will take up its most inclined position (Figure 7). For this position of the swash plate the working conditions of the connecting rods 20 and of the free-wheel mechanisms are shown in Figures 13-16. According to Figure 13 the front free-wheelmechanism 12 together with the lower connecting rod 20 is in the middle of its working stroke, the front free-wheel mechanism 12 together with the upper connecting rod at the commencement of its working stroke, whilst the rear free-wheel mechanism 12 together with the upper connecting rod 20 is in the middle of its no load stroke, and the rear free-wheel mechanism 12 together with the lower connecting rod at the commencement of its no-load stroke.

After the swash plate has been rotated through 90"., the parts take up the positions in which they are illustrated in Figure 14, in which the front free-wheel mechanism 12 together with the upper connecting rod is in the middle of its working stroke, the front free-wheel mechanism 12 together with the lower connecting rod at the commencement of the no-load stroke, whereas the rear freewheel mechanism 12 is at the commencement of its working stroke and the rear free-wheel mechanism 12 in the middle of its no-load stroke. After a further quarter revolution of the swash plate (Figure 15 the front freewheel mechanism 12 is at the eginning of its no-load stroke and the front free-wheel mechanism 12 in the middle of its no-load stroke whilst the rear free-wheel mechanism 12 is in the middle of its working stroke and the rear free-wheel mechanism 12 at the commencement of its working stroke. After a further quarter revolution of the swash plate (Figure 16) the front free-wheel mechanism 12 is in the middle of its no-load stroke and the front free-wheel mechanism 12 at the commencement of its working stroke whereas the rear free-wheel mechanism 12 is at the commencement of its noload stroke and the rear free-wheel mechanism 12 in the middle of its working stroke. The working free-wheel mechanisms or those about to effect their working strokes together with their connecting rods are marked in thick lines for the sake of clearness. It will be evident from Figures 13-16, that among" the two pairs of free-wheel mechanisms one free-wheel mechanism effects a working stroke whilst another is in the middle of its working stroke so that the free-wheel mechanisms before the end of their working stroke are relieved in pairs and the working operation is never interrupted.

' The swash plate 5 is illustrated diagrammatically in these figures. The directions of movement of the connecting rods 20 are indicated b arrows. In following these con ditions o movement, it is of course necessary to become conversant with the fact that the front free-wheel mechanisms during their working strokes must operate in the reverse direction to the corresponding rear freewheel mechanisms, which is indicated by the direction of the arrows in the connecting rods shown in thick lines, for the front free-wheel mechanism operate on the front and the rear on the rear of the oppositely rotating bevel wheels 11. In this manner a continuous rotary movement on the driven shaft 2 in the same direction is obtained, the speed of the driven shaft 2 depending upon the inclination of the swash plate 5, inasmuch as the working stroke of the free-wheel mechanisms varies in accordance with the inclination of the swash plate 5.

If the controlling body 25 is moved further in the direction ofthe arrow 9:, the swash plate 5 is gradually again raised to a perpendicular position by means of the toothed segments 27, whilst the internally toothed portion 37 of the controlling body 25 comes into engagement with the toothed wheel 35 and thus establishes direct connection between the .driving shaft 1 and the driven shaft 2. This ,mits of a transition from direct drive to indirect drive that is to say in reverse order from direct operation and through a gradual change of speed up to a stand-still when the swash plate 5 has moved back into the 13051-- tion in which it is illustrated in Figure 6.

By movement of the controlling body 25 it is thus possible to obtain any desired speed of the shaft 2 from zero to a definite maximum, the change from one speed to another being effected smoothly. If necessary the controlling body 25 may, by means of an ad-' justing device, be secured in any desired position.

So far only one direction of rotation has been assumed for the shaft 2. In order to enable the direction of rotation of the shaft 2 to be reversed when required, the pairs of free-wheel mechanisms 12, 12 shown in Figures 11 and 12 are provided with reversing members 40 adapted to be rotated from the outside of the casing, these members being provided with recesses or openin s 41 in which the jamming rollers 16, are reely located, so that by rotating the members 40 in the one or theother direction the rollers 16 can be moved into different positions with respect to the surfaces 14 of the wheel axle 14, with the result that the rollers are jammed in the one or the other direction. The members 40 are provided with toothed wheels 42 (Figures 1 and 5) and by means of a mem ber 43 two toothed rods 44 can be brought into engagement with these toothed wheels 42 and thus be caused to rotate. The degree of rotation of the toothed wheels 42 is restricted. being just sufiicient to effect the reversal of the jamming rollers 16 by means of the "memtransverse trunnion on said driving shaft for carryingsaid swash plate, means connecting said swash plate to said free-wheel, or ratchet mechanisms so as to produce an overlapping operation thereof, 'a rotary and axially movable controlling body connected to the driving shaft, means to shift same axially on the driving shaft, means movably interconnecting said controlling body and swash plate, arranged to bias the swash plate on axial displacement of said controlling body, for changing the amplitude of the operating stroke of said free-wheel or ratchet mechanisms, a toothed wheel clutch member on the shaft to be driven and a coupling gear clutch member onsaid controlling body to finally mesh with said toothed wheel clutch member for the purpose described.

2. A variable speed apparatus, comprising in combination with a rotary driving shaft and a rotary shaft to be driven, alternately operatable free-wheel or ratchet mechanisms, connectionmeans between said freewheel or ratchet mechanisms andthe shaft to be driven, a pivotally mounted swash plate,

a transverse trunnion on said driving. shaft for carrying said swash plate, means'connecting said swash plate to said free-wheel or ratchet mechanisms so as to produce an overlapping operation thereof, a rotary andax ially movable controlling body connected to the driving shaft, means to shift same axially on the driving shaft, toothed gearing memclutch member, for the purpose described. co

3. A variable speed apparatus, comprising in combination with a rotary driving shaft and a rotary shaft to be driven, alternately operatable free wheel or ratchet mechanisms, connectionmeans between said freewheel or ratchet mechanism and the shaft to be driven, a pivotally mounted swash plate, a transverse trunnion on said driving displacement of said controlling body,ffor' changing the amplitude of the operating stroke of said free-wheel or ratchet mechanisms, a toothed wheel clutch member on the shaft to be driven and a coupling gear clutch member on said controlling body to finally mesh with said toothed wheel clutch mem her, for the purpose described. I

4. A variable speed apparatus, comprising in combination with a rotary driving shaft and a rotary shaft to'be driven, alternately operatable free-wheel or ratchet mechanisms, I

connection means between free-wheel or ratchet mechanisms andthe shaft to be driven, a pivotally mounted swash plate, a transverse trunnion on said driving shaft for carrying said swash plate, means connecting said swash plate to said free-wheel or ratchet mechanisms so as to produce an overlapping operation thereof, a rotary and axially movable controlling body connected to the driving. shaft, means to shift same axially on the driving shaft, toothed gearing segments carried by the driving shaft, the one connected to the swash plate, the other connected to the shaft and associated with said controlling body, a

'cam device on said body, arranged to operate said gearing segments and to thus bias the swash plate on axialdisplacement'of said controlling body, for changing the amplitude of the operating stroke of said free-wheel or ratchet mechanisms, a toothed wheel clutch member on the shaft tobe driven and a coupling gear clutch member on said' controlling body to finall mesh with said toothed wheel clutch mem er, for the purpose described,

5. A- variable speed apparatus, comprising in combination with\a rotary driving shaft and a rotary shaft to be driven, alternately operatable free-wheel or ratchet mechanisms, connection means between said freewheel or ratchet-mechanism and the shaft to be driven, a pivotally mounted swash plate, a transverse trunnion on said driving shaft for carrying said swash plate, means connecting said swash plate to said freewheel or ratchet mechanisms'so as to produce an overlapping o eration thereof, a rotary and ax1a1ly ,mova le controlling body connected to the driving shaft, means to shift same axially on the drivin shaft, means for guiding said controlling ody in a direction parallel to the axis'of rotation of the driving shaft, without preventing its rotation, means movably interconnecting said controlling body and swash plate, arranged to biasthe swash plate on axial displacement of said controlling body, 'for changing the amplitude of the operating stroke of said free-wheel or ratchet mechanisms, a toothed wheel clutch member on the shaft to be driven and a coupling gear clutch member on said controlling body to finally mesh with said toothed wheel clutch, member, for the purpose described.

6. A variable speed apparatus, comprising in combination with a rotary driving shaft and a rotary shaft to be driven, alternately operatable free-wheel or ratchet mechanisms, the latter being of the jamming type with jamming elements and having adjustable reversing members for reversing the amming operatlon thereof, connection means between said free-wheel or ratchet mechanisms and the shaftto be driven, a pivotally mounted swash plate, a transverse trunnion on said driving shaftfor carrying said swash plate, means connecting said swash plate to said free-wheel or ratchet mechanisms so as to produce an overlapping operation thereof, a rotary and axially movable controlling body connected to the driving shaft, means to shift same axially on the driving shaft, meansmovably interconnecting said controlling body and swash plate, arranged to bias the swash plate on axial displacement of said controlling body, for changing the amplitude of the operating stroke of said free-wheel or ratchet mechanisms, a toothed wheel clutch member on the shaft to be driven and a coupling gear clutch member on said controllin-g body to finally mesh with said toothed wheel clutch member, for the purpose described.

In witness whereof Ihave hereunto signed my name this 26th day of November, 1928.

' ADOLF'LAUB. 

